ISO 7165 Fire Fighting - Portable Fire Extinguishers - Performance and Construction

The standard “ISO 7165 Firefighting - Portable fire extinguishers - Performance and construction”, developed by the International Organization for Standardization (ISO), describes the essential requirements aimed at ensuring the safety, reliability and performance of portable fire extinguishers. This standard applies to a fully charged extinguisher with a maximum mass of 20 kg. Subject to local acceptance, the application may be extended to extinguishers with a total mass of up to 25 kg when fully charged.

For the purposes of this standard, the following terms and definitions apply:

• Batch refers to a group of the same product produced in the same production line using the same batch of material in the same production shift.
• The cumulative range refers to the range when 50 percent of the extinguishing medium is expelled.
• The extinguisher load is the mass or volume of the extinguishing medium contained in the extinguisher. It is expressed in volume (litres) for water-based extinguishers and in mass (kilograms) for other extinguishers.
• Classification of fires is the grouping of fires according to their characteristics:
  • Class A includes solids, generally of organic nature, in which combustion normally occurs by the formation of glowing embers.
  • Class B includes liquids or liquefiable solids.
  • Class C includes gases.
  • Class D includes metals.
  • Class F includes cooking media (vegetable or animal fats and oils) in cooking appliances.
• Clean agent refers to an electrically non-conductive gas or vaporizing liquid fire. It is an extinguisher that leaves no residue when vaporized.
• Full discharge is the point in the extinguisher discharge where the internal pressure equalizes with the external pressure and the valve control is held fully open.
• A single-use extinguisher is a non-rechargeable extinguisher that is not designed to be recharged in the field or in the factory, but is intended to be discarded after use.
• The effective discharge time is the time from the beginning of the discharge of the quenching medium in the nozzle to the gas point of the discharge flow with the control valve fully open.
• The extinguishing medium is the substance contained in the extinguisher that causes extinguishing.

Extinguishers should be classified according to the type of extinguishing medium they contain. Currently, the main classes of extinguishers include:

• Water based
• Powder
• Carbon dioxide
• Clean substances

These classes of extinguishers can be further subdivided. For example, water-based extinguishers may contain pure water or water containing additives such as wetting agents, viscosity enhancers, flame retardants, foaming agents, wet chemicals. Water-based extinguishers containing different types of freezing point depressants, including foam, should be treated as separate and distinct models for the purposes of fire rating tests and testing of operating temperature range and electrical conductivity. All other requirements for the design and construction of water-based extinguishers apply to all models, regardless of content.

The extinguishing media, propellants and filling requirements are determined as follows:

• Carbon dioxide: Carbon dioxide used in extinguishers must comply with the ISO 5923 standard.
• Clean agents: Clean agents used in extinguishers must comply with the annexes of this standard or be regulated by a country's national environmental regulatory agency. In some countries, the production and use of clean agents is regulated by a protocol or national regulations.
• Powders: Powders used in extinguishers must comply with the ISO 7202 standard, except for powders used on class D fires.
• Foam concentrates: Foam concentrates used in extinguishers must comply with ISO 7203. There is no international standard covering non-foaming additives, which are sometimes added to water to produce antifreeze, wetting or other special properties. However, such extinguishers are included in the category of water-based extinguishers.
• Water-based agents: When the pH of the extinguishing agent exceeds 9,5, a warning statement should be required on the extinguisher nameplate.

For stored pressure and cartridge extinguishers, the propellants shall be air, argon, carbon dioxide, helium or nitrogen, or mixtures of these gases, with a maximum dew point of minus 55 degrees. Non-flammable tracers may be added to the propellant to facilitate leak detection. The percentage of tracer should be specified by the manufacturer and verified by a testing laboratory, but for stored pressure, water-based extinguishers, the propellant is not required to meet the above dew point.

For carbon dioxide extinguishers the maximum filling density shall not exceed 0,75 kg/l. For clean agent fire extinguishers the filling density shall not exceed the values ​​given in the annexes to this standard, as appropriate. These filling densities may be subject to national pressure vessel regulations.

The actual load of an extinguisher must be within the limits given in the standard for water-based extinguishers, powder extinguishers, clean agent extinguishers and carbon dioxide extinguishers.

For low-pressure extinguishers, the test pressure shall be 1,43 × pms but in no case less than 2 MPa (20 bar). For low-pressure extinguishers, the minimum burst pressure shall be 2,7 × pms but in no case less than 5,5 MPa (55 bar).

Our organization, which has been trying to support businesses from every sector with its testing, measurement, analysis and evaluation studies carried out in a wide range for years, has a strong staff that closely follows the developments in the world in the field of science and technology and constantly improves itself. In this context, testing services in accordance with the "ISO 7165 Fire Fighting - Portable Fire Extinguishers - Performance and Structure" standard are also provided to businesses.